Add optional signature (proof) checking when reading records. Lightly
tested. Seems to do the right thing if the signature does verify, but
fails incorrectly if it does not. Does not do any hash chain checking
Add -o flag on gdp-reader to set output file.
Clean up exit statuses for apps to make it easier to use them in
Implement gdp_gcl_read_async. This also fixes some obscure problems
with other asynchronous operations, and tweaks debugging flags to make
it easier to pick out the operations you want to see.
First cut at read-by-timestamp. Adds Berkeley DB as a dependency (two
versions supported). The interface still isn't quite right; in
particular, subscribe and multiread don't take timestamps. This should
be remedied before this code is released.
Add -q flag to gdp-reader to suppress all metadata output; this allows
it to be piped into another program to read the data.
Rename reader-test => gdp-reader and writer-test => gdp-writer. They
aren't test programs any more.